US11261731B1

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Info

Publication number: US11261731B1
Application number: US15/699,504
Authority: US
Inventors: Phillip Sollami
Original assignee: Sollami Co
Current assignee: Sollami Co
Priority date: 2014-04-23
Filing date: 2017-09-08
Publication date: 2022-03-01

Abstract

A bit assembly includes a base block and a bit holder having a body portion and a shank. The body portion and the shank being coaxial and including a bore extending from a forward end of the body portion to the distal end of the shank. The shank further includes at least two segments, a first segment and a second segment. The second segment is subject to the first segment and includes a taper towards the top segment. The base block includes a base and a shortened front end. The shortened front end having a forward face and a rear face. The forward face including an indentation and the rear face including a slot extending axially inward from the rear face to a position mediate the forward face.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and is a continuation-in-part of U.S. Provisional Application No. 61/983,291, filed Apr. 23, 2014, claims priority to and is a continuation-in-part of U.S. Non-provisional application Ser. No. 14/690,679, filed Apr. 20, 2015, now U.S. Pat. No. 10,370,966, issued Aug. 6, 2019, claims priority to and is a continuation-in-part of U.S. Provisional Application No. 62/100,764, filed Jan. 7, 2015, and claims priority to and is a continuation-in-part of U.S. Non-provisional application Ser. No. 14/959,551, filed Dec. 4, 2015, now U.S. Pat. No. 10,337,324, issued Jul. 2, 2019, to the extent allowed by law and the contents of which are incorporated herein by reference in their entireties.

TECHNICAL FIELD

This disclosure relates to bit assemblies for road milling, mining, and trenching equipment, and more particularly, to a bit holder for use in shortened depth bore bit holder blocks.

BACKGROUND

Road milling, mining, and trenching equipment utilizes bits traditionally set in a bit assembly having a bit holder and a bit holder block. In one embodiment, the bit is retained by the bit holder and the bit holder is retained in the bit holder block. In another embodiment a unitary bit/holder is retained in the bit holder block. A plurality of the bit assemblies are mounted on the outside of a rotatable drum in staggered positions, typically in a V-shaped or spiral configuration, in an effort to create the smoothest road milling. The combinations of bit assemblies have been utilized to remove material from the terra firma, such as degrading the surface of the earth, minerals, cement, concrete, macadam or asphalt pavement. Individual bits, bit holders, and bit holder blocks may wear down or break over time due to the harsh road degrading environment. Additionally, the bit holder or the unitary bit/holder may be ejected out of the bit holder block bore due to the harsh road degrading environment. A need has developed to provide an improved bit holder and unitary bit/holder that makes a sufficient radial connection with the bit holder block bore to prevent the bit holder and/or unitary bit/holder from being ejected out of the bit holder block bore during harsh operations.

SUMMARY

This disclosure relates generally to bit assemblies for road milling, mining, and trenching equipment. One implementation of the teachings herein is a bit holder that includes a body having a bottom; and a generally cylindrical shank depending axially from the bottom of the body, the shank including: a top segment subjacent the bottom of the body, the top segment configured to make contact along a diameter with a bore of a base block; a mediate segment subjacent the top segment, the mediate segment including a taper towards the top segment; and an axially extending slot through a sidewall of the shank extending upwardly from a distal end of the shank.

One implementation of the teachings herein is a combination bit holder and base blocks that includes a base block including a receiving portion opposite a base, the receiving portion including a bore axially extending through the receiving portion; and a bit holder including a body having a bottom; and a generally cylindrical shank depending axially from the bottom of the body, the shank including: a top segment subjacent the bottom of the body, the top segment configured to make contact along a diameter with a bore of a base block; a mediate segment subjacent the top segment, the mediate segment including a taper towards the top segment; and an axially extending slot through a sidewall of the shank extending upwardly from a distal end of the shank.

These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the appended claims and the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The various features, advantages, and other uses of the apparatus will become more apparent by referring to the following detailed description and drawings, wherein like reference numerals refer to like parts throughout the several views. It is emphasized that, according to common practice, the various features of the drawings are not to-scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

FIG. 1 is a rear elevation view of a first embodiment of a bit assembly, without a bit, showing a bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 2 is a top elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 3 is a side elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 4 is a front elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 5 is a rear horizontal perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 6 is a front/side vertical perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 7 is a front vertical perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 8 is a rear perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 9 is a side perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 10 is a front perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 11 is an exploded top elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 12 is an exploded side elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 13 is an exploded side perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 14 is an exploded top/side perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 15 is an exploded side perspective view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 16 is a bottom elevation view of the first embodiment of the bit assembly, without a bit, showing the bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 17 is a cross-sectional side elevation view taken along Line N-N ofFIG. 16 of the first embodiment of the bit assembly, without a bit, showing a bit holder and bit holder block in accordance with implementations of this disclosure;

FIG. 18 is a detail cross-sectional side elevation view of the first embodiment of the bit assembly, without a bit, showing Detail R of the bit holder and bit holder block ofFIG. 17 in accordance with implementations of this disclosure;

FIG. 19 is a side elevation view of a second embodiment of a bit assembly, showing a bit, a bit holder and a base block in accordance with implementations of this disclosure;

FIG. 20 is a side perspective view of the second embodiment of the bit assembly, showing a bit, bit holder, and base block in accordance with implementations of this disclosure;

FIG. 21 is a side elevation view of the base block of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 22 is a front elevation view of the base block of the second embodiment of the bit assembly, taken along Axis A ofFIG. 21, in accordance with implementations of this disclosure;

FIG. 23 is a front perspective view of the base block of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 24 is a side perspective view of the base block of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 25 is a top elevation view of the bit holder of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 26 is a side perspective view of the bit holder of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 27 is a side elevation view of the bit holder of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 28 is a front elevation view of the bit holder of the second embodiment of the bit assembly in accordance with implementations of this disclosure;

FIG. 29 is an exploded side perspective view of the second embodiment of the bit assembly, showing the bit, the bit holder, and the base block, in accordance with implementations of this disclosure;

FIG. 30 is an exploded top elevation view of the second embodiment of the bit assembly, showing the bit, the bit holder, and the base block, in accordance with implementations of this disclosure; and

FIG. 31 is an exploded side elevation view of the second embodiment of the bit assembly, showing the bit, the bit holder, and the base block, in accordance with implementations of this disclosure.

DETAILED DESCRIPTION

Road milling, mining, and trenching equipment utilizes bits traditionally set in a bit assembly having a bit holder and a bit holder block. In one embodiment, the bit is retained by the bit holder and the bit holder is retained in the bit holder block. In another embodiment a unitary bit/holder is retained in the bit holder block. A plurality of the bit assemblies are mounted on the outside of a rotatable drum in staggered positions, typically in a V-shaped or spiral configuration, in an effort to create the smoothest road milling. To provide a smoother surface, the size of the bit holder block can be reduced, such as by reducing the axial dimensions of the bit holder block, to allow the bit assemblies to be placed closer together. Such narrowed bit holder blocks, herein after referred to as base blocks, allow closer center-to-center axial bit tip position with the V-shaped or spiral configurations, thereby resulting in a smoother road surface. One important aspect of the present disclosure is providing a base block with narrowed dimensions to reduce the distance axial bit tip orientation. Another important aspect of the present disclosure is providing an improved bit holder and unitary bit/holder that makes a sufficient radial connection with a bore of the base block bore to prevent the bit holder and/or unitary bit/holder from being ejected out of the base block bore during harsh operations. A further important aspect of the present disclosure is providing an improved bit holder and unitary bit/holder that forms a sufficient interference fit to engage a continuous diameter of the base block bore.

Referring toFIGS. 1-18, a first embodiment of abit assembly10, without a bit, comprises abit holder12 and abase block14. Thebit holder12 includes abit holder body16 and ashank18 axially depending from the bottom of thebit holder body16. Thebit holder body16 is generally annular in shape and comprises an annular or generally cylindricalupper body portion20 axially extending from a flat annulartop surface22. Subjacent theupper body portion20 is amiddle portion24 that extends axially and radially outwardly to a radially extending generallycylindrical tire portion26. Themiddle portion24, in this illustrated embodiment, has an arcuate shape. In other embodiments, themiddle portion24 can have a frustoconical shape, a convex shape, or a concave shape.

Adjacent thetire portion26 is a taperedportion28, shown inFIG. 18, that ends in aflange30, such as a flat annular flange, shown inFIGS. 11-14 and 18, that denotes the bottom of thebit holder body16. Thetire portion26 includes a pair of tapered

cutouts

32,34, or wedge-shaped undercuts, shown inFIGS. 2, and 11, to provide access and leverage for a tool to extract thebit holder12 from thebase block14. The

tapered cutouts

32,34 are formed into thetire portion26 and extend from theflange30 subjacent to thetire portion26. The

tapered cutouts

32,34 include a pair of parallel flat vertical

inner surfaces

36,38, respectively, as shown inFIGS. 2 and 11, and a pair of flat tapered

top surfaces

40,42, respectively, as shown inFIGS. 2 and 11. The outer edge of the flat tapered

top surfaces

40,42 is each arcuate in shape to follow the periphery of thetire portion26. A pair of

notches

44,46, shown inFIGS. 2, 4-7, 9-11, and 13-15, are formed into thebit holder body16 and extend from the flat annulartop surface22 through theupper body portion20 and themiddle portion24, terminating at a point within themiddle portion24. The

notches

44,46 provide access and leverage for a tool to extract, or knock out, a bit from thebit holder body16.

There is a standard interference between the increased diameter shortenedtop segment52 of theshank18 of thebit holder12 and a corresponding portion of the base block bore68. This uppertop segment52 may, in another embodiment, be tapered to conform with the angle of taper of the top of the base block bore68 to provide an annular surface interference rather than an annular line interference. The lowertapered segment60 includes a reverse taper that increases toward the bottom end of the lowertapered segment60. This “reverse taper” only has to be a less tapered portion than that of the adjacent corresponding portion of the base block bore68. In other words, if the taper that portion of the base block bore68 is one degree per side, the reverse taper of the lowertapered segment60 would only have to be something less than that, i.e., ½ degree per side. If the base block bore68 is cylindrical, the reverse taper portion of the lowertapered segment60 would only have to be a negative taper of ½ degree, 1 degree, etc. per side. The reason for the reverse taper is to move the position at which a greater interference force is exerted at thedistal end50 of theshank18. By using a lesser taper on thebit holder shank18 that that of the base block bore68, the area of greater interference or holding force between the base block bore68 and thebit holder shank18 may be moved lower on the shank neardistal end50 and may also be spread over a greater axial length than that utilized in the prior art.

Thebase block14 also includes anarcuate bore68 extension71 (FIGS. 5, 8, 11, 13-15, and 18) starting at an inner portion of the base block bore68 subjacent therear face73 of the shortenedfront end66 and extending toward a rear75 (FIGS. 2, 5, 8, 9, 11, 13, and 14) of thebase block14. Theextension71 does not serve a function when thebase block14 is used with a shortenedshank bit holder12. A bit holder having a shortened 1½ inch long shank that shows sufficient wear that it needs to be replaced may not only be replaced with another bit holder having a 1½ inch long shank but may also be replaced by what may be termed a standard “quick change” bit holder having a 2⅝ inch long shank. Over time the extreme forces from cutting conditions will wear the base block bore68 andbit holder shank18 such that the shortenedshank bit holder12 may not successfully be retained in the base block bore68 and the shortenedshank bit holder12 must be replaced with a standard 2⅝ inch length shank bit holder (not shown). Theextension71 engages the 2⅝ inch long shank of the standard bit holder adjacent its distal end and provides sufficient sideways force against that portion of the shank to retain the standard bit holder in thebase block14.

The shortenedfront end66 also includes a pair of flat

vertical sides

70,72, shown inFIGS. 1, 4-6 and 9-13, and 15, that extend near and/or adjacent thebase64. The flat

vertical sides

70,72 reduce the dimensions of thebase block14 width and allow bit assemblies to be positioned in closer center-to-center axial bit tip orientation in order to degrade the road to a smoother surface. Avertical distance74, shown inFIG. 13, between atop portion76 and abottom portion78 of the shortenedfront end66 is greater than ahorizontal distance80, shown inFIG. 13, between the flat

vertical sides

70,72 of the shortenedfront end66.

Referring toFIGS. 19-31, a second embodiment of abit assembly100, shown with abit102 inFIGS. 19, 20, and 29-31, comprises thebit holder12, as described in the first embodiment of thebit assembly10, and abase block104. Thebase block104 comprises abase106 and a shortenedfront end108. The base106 can be flat or slightly concave to fit a drum or additional mounting plates on which a singular or a plurality of base blocks can be mounted. The shortenedfront end108 includes a base block bore110, shown inFIGS. 22-24 and 29, that is symmetrical with theshank18 along a centerline. The shortenedfront end108 and the base block bore110 extending axially through the shortenedfront end108 are shortened to approximately 1.5 inches in length, in this embodiment, by removing material from the rear of the shortenedfront end108. The shortenedfront end108 includes, in this embodiment, an indentation112 (FIGS. 22-24 and 29) on afront face114 of thebase block104. The shortenedfront end108 also includes, in this embodiment, a slot116 (FIGS. 22-24) decreasing in radial size from a rear face118 (FIG. 21) of the shortenedfront end108 to a position mediate thefront face114. Theslot116 provides added room for a punch (not shown) to operate and push the shank of thebit102 out of thebit holder12.

Thebase block104 also includes anarcuate bore110 extension120 (FIG. 30) starting at an inner portion of the base block bore110 subjacent therear face118 of the shortenedfront end108 and extending toward a rear122 (FIG. 30) of thebase block104. As mentioned in the first embodiment, theextension120 does not serve a function when thebase block104 is used with a shortenedshank bit holder12. Once the shortenedshank bit holder12 is not able to be successfully retained in the base block bore110, the shortenedshank bit holder12 is replaced with a standard 2⅝ inch length shank bit holder (not shown). Theextension110 engages the 2⅝ inch long shank of the standard bit holder adjacent its distal end and provides sufficient sideways force against that portion of the shank to retain the standard bit holder in thebase block104.

The perimeter of thefront face114 of the shortenedfront end108 is annular, circular, or cylindrical, in this embodiment, and thefront face114 is perpendicular to the base block bore110. Avertical distance124, shown inFIG. 22, between atop portion126 and abottom portion128 of the shortenedfront end108 is approximately the same as or equal to ahorizontal distance130, shown inFIG. 22, between afirst side portion132 and asecond side portion134 of the shortenedfront end108.

When assembled,slot56 allows theshank18 to radially compress when inserted into the first embodiment or the second embodiment of the base block bore68,110 of the shortened

front end

66,108, respectively, forming a sufficient interference fit to engage a continuous diameter between theshank18 and the base block bore68,110, respectively. The force between the diametrically contractedshank18 and the base block bore68,110 maintains and retains thebit holder12 in the

base block

14,104 and provides a sufficient radial connection to prevent theshank18 from moving out of the base block bore68,110 during use. Furthermore,top segment52 of theshank18 provides additional radial compression force and additional contact between thetop segment52 and the base block bore68,110, thereby allowing for a greater increase of radial contact which results in a higher distributed radial force maintaining theshank18 within the

bore

68,110 of the

base block

14,104, respectively. At least ⅓ of the axial length, and/or at least ½ inch, of theshank18 between theflange30 and the distal end of thetop segment52 of theshank18, or a forward end77 (FIG. 18) of theslot69, in this illustrated embodiment, contacts the

bore

68,110 of the

base block

14,104, respectively, and provides greater radial length contact resulting in greater radial force. The interference contact zones between the tapered bore68,110 of the

base block

14,104, respectively, and the corresponding surface of theshank18 is at least 50% of the available axial contact length of the distal end portion of theshank18 and at least 50% of the available axial contact length of the forward portion of theshank18. Thebit holder12 and the

base block

14,104 are assembled together to form the

bit assembly

10,100, respectively. Thebit holder12, including thebit holder body16,shank18, and bit holder bore48, and the

base block

14,104, including the

base

64,106, shortened

front end

66,108, and base block bore68,110, respectively, are all axially aligned when assembled together to form thebit assembly10.

While the present disclosure has been described in connection with certain embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.

Claims

What is claimed is:

1. A bit holder comprising:

a body comprising a bottom and an annular undercut disposed within the bottom; and

a generally cylindrical shank depending axially from the bottom of the body, the shank comprising:

a top segment axially extending from the annular undercut, the top segment subjacent the bottom of the body, at least one of at least ⅓ of an axial length of the top segment and at least ½ inch of the axial length of the top segment adapted to make an interference fit along a circumference with a corresponding portion of a bore of a base block;

a mediate segment adjacent the top segment, the mediate segment being inwardly tapered from a distal end of the mediate segment towards a first location and being outwardly tapered from the first location towards a second location subjacent a distal end of the top segment, a diameter of the mediate segment at the first location being less than a diameter of the top segment; and

an axially extending slot through a sidewall of the shank extending upwardly from a distal end of the shank.

2. The bit holder ofclaim 1, wherein an axial length of the body is greater than an axial length of the shank.

3. The bit holder ofclaim 1, further comprising:

a lower segment adjacent the mediate segment, the lower segment tapered outwardly as it axially extends towards the distal end of the shank; and

a distal segment adjacent the lower segment and adjacent the distal end of the shank.

4. The bit holder ofclaim 3, wherein the lower segment is adapted to make an interference fit at a first corresponding location of the bore of the base block and the top segment is adapted to make an interference fit at a second corresponding location of the bore of the base block.

5. The bit holder ofclaim 3, wherein a first diameter of the lower segment is greater than a second diameter of the distal segment.

6. The bit holder ofclaim 3, wherein at least 50% of an axial length of the lower segment is adapted to form an interference fit with a corresponding portion of the bore of the base block.

7. The bit holder ofclaim 1, wherein a first diameter of the top segment is at least a second diameter of the mediate segment.

8. The bit holder ofclaim 1, further comprising:

a flange on the bottom of the body, the flange laterally extending from the annular undercut, the annular undercut comprising one of an annular rounded undercut and a cylindrical rounded undercut.

9. The bit holder ofclaim 1, further comprising:

a central bore extending axially inwardly from the distal end the shank to a forward end of the body.

10. The bit holder ofclaim 1, wherein an axial length of the shank is at least an axial length of the body.

11. The bit holder ofclaim 1, wherein an axial length of the body is one of less than and equal to an axial length of the shank.

12. The bit holder ofclaim 1, wherein an axial length of the shank is approximately 1 ½ inches.

13. The bit holder ofclaim 1, wherein at least 50% of the axial length of the top segment is adapted to form an interference fit with a corresponding portion of the bore of the base block.

14. A combination bit holder and base block comprising:

a base block comprising a receiving portion opposite a base, the receiving portion including a bore axially extending through the receiving portion; and

a bit holder comprising:

a top segment axially extending from the annular undercut, the top segment subjacent the bottom of the body, at least one of at least ⅓ of an axial length of the top segment and at least ½ inch of the axial length of the top segment adapted to make an interference fit along a circumference with a corresponding portion of the bore of the base block;

15. The combination ofclaim 14, wherein an axial length of the body is greater than an axial length of the shank.

16. The combination ofclaim 14, further comprising:

17. The combination ofclaim 16, wherein the lower segment is adapted to make an interference fit at a first corresponding location of the bore of the base block and the top segment is adapted to make an interference fit at a second corresponding location of the bore of the base block.

18. The combination ofclaim 16, wherein a first diameter of the lower segment is greater than a second diameter of the distal segment.

19. The combination ofclaim 16, wherein a first diameter of the top segment is at least a second diameter of the mediate segment.

20. The combination ofclaim 16, wherein at least 50% of an axial length of the lower segment is adapted to form an interference fit with a corresponding portion of the bore of the base block.

21. The combination ofclaim 14, further comprising:

22. The combination ofclaim 14, further comprising:

23. The combination ofclaim 14, wherein the receiving portion includes one of a pair of flat vertical sides and a pair of rounded sides extending from the receiving portion to the base.

24. The combination ofclaim 14, further comprising:

an extension of an arcuate segment of the bore extending from a rear of the receiving portion, the extension of the arcuate segment of the bore providing an interference with a device capable of being securely mounted through the bore and outwardly of a rear of the receiving portion.

25. The combination ofclaim 14, wherein an axial length of the shank is at least an axial length of the body.

26. The combination ofclaim 14, wherein an axial length of the body is one of less than and equal to an axial length of the shank.

27. The combination ofclaim 14, wherein an axial length of the shank is approximately 1½ inches.

28. The combination ofclaim 14, wherein at least 50% of the axial length of the top segment is adapted to form an interference fit with a corresponding portion of the bore of the base block.

29. The combination ofclaim 14, further comprising:

a semi-circular angled slot extending inwardly from a rear face of the receiving portion, the slot enclosed within a sidewall of the receiving portion, the slot decreasing in size from the rear face of the receiving portion to a position mediate a front face of the receiving portion and the rear face of the receiving portion.

30. The combination ofclaim 14, further comprising:

an indentation disposed on a front face of the receiving portion axially above the bore.

31. The combination ofclaim 14, wherein at least one of the receiving portion and the bore comprise an axial length of approximately 1½ inches.